We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict Trs:
  { fst(X1, X2) -> n__fst(X1, X2)
  , fst(0(), Z) -> nil()
  , fst(s(X), cons(Y, Z)) ->
    cons(Y, n__fst(activate(X), activate(Z)))
  , activate(X) -> X
  , activate(n__fst(X1, X2)) -> fst(X1, X2)
  , activate(n__from(X)) -> from(X)
  , activate(n__add(X1, X2)) -> add(X1, X2)
  , activate(n__len(X)) -> len(X)
  , from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , add(X1, X2) -> n__add(X1, X2)
  , add(0(), X) -> X
  , add(s(X), Y) -> s(n__add(activate(X), Y))
  , len(X) -> n__len(X)
  , len(nil()) -> 0()
  , len(cons(X, Z)) -> s(n__len(activate(Z))) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

The weightgap principle applies (using the following nonconstant
growth matrix-interpretation)

The following argument positions are usable:
  Uargs(s) = {1}, Uargs(cons) = {2}, Uargs(n__fst) = {1, 2},
  Uargs(n__add) = {1}, Uargs(n__len) = {1}

TcT has computed the following matrix interpretation satisfying
not(EDA) and not(IDA(1)).

     [fst](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
               [0] = [4]                  
                                          
             [nil] = [0]                  
                                          
           [s](x1) = [1] x1 + [0]         
                                          
    [cons](x1, x2) = [1] x2 + [0]         
                                          
  [n__fst](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
    [activate](x1) = [1] x1 + [0]         
                                          
        [from](x1) = [1]                  
                                          
     [n__from](x1) = [0]                  
                                          
     [add](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
  [n__add](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
         [len](x1) = [1] x1 + [0]         
                                          
      [n__len](x1) = [1] x1 + [0]         

The order satisfies the following ordering constraints:

               [fst(X1, X2)] =  [1] X1 + [1] X2 + [0]                      
                             >= [1] X1 + [1] X2 + [0]                      
                             =  [n__fst(X1, X2)]                           
                                                                           
               [fst(0(), Z)] =  [1] Z + [4]                                
                             >  [0]                                        
                             =  [nil()]                                    
                                                                           
     [fst(s(X), cons(Y, Z))] =  [1] Z + [1] X + [0]                        
                             >= [1] Z + [1] X + [0]                        
                             =  [cons(Y, n__fst(activate(X), activate(Z)))]
                                                                           
               [activate(X)] =  [1] X + [0]                                
                             >= [1] X + [0]                                
                             =  [X]                                        
                                                                           
  [activate(n__fst(X1, X2))] =  [1] X1 + [1] X2 + [0]                      
                             >= [1] X1 + [1] X2 + [0]                      
                             =  [fst(X1, X2)]                              
                                                                           
      [activate(n__from(X))] =  [0]                                        
                             ?  [1]                                        
                             =  [from(X)]                                  
                                                                           
  [activate(n__add(X1, X2))] =  [1] X1 + [1] X2 + [0]                      
                             >= [1] X1 + [1] X2 + [0]                      
                             =  [add(X1, X2)]                              
                                                                           
       [activate(n__len(X))] =  [1] X + [0]                                
                             >= [1] X + [0]                                
                             =  [len(X)]                                   
                                                                           
                   [from(X)] =  [1]                                        
                             >  [0]                                        
                             =  [cons(X, n__from(s(X)))]                   
                                                                           
                   [from(X)] =  [1]                                        
                             >  [0]                                        
                             =  [n__from(X)]                               
                                                                           
               [add(X1, X2)] =  [1] X1 + [1] X2 + [0]                      
                             >= [1] X1 + [1] X2 + [0]                      
                             =  [n__add(X1, X2)]                           
                                                                           
               [add(0(), X)] =  [1] X + [4]                                
                             >  [1] X + [0]                                
                             =  [X]                                        
                                                                           
              [add(s(X), Y)] =  [1] X + [1] Y + [0]                        
                             >= [1] X + [1] Y + [0]                        
                             =  [s(n__add(activate(X), Y))]                
                                                                           
                    [len(X)] =  [1] X + [0]                                
                             >= [1] X + [0]                                
                             =  [n__len(X)]                                
                                                                           
                [len(nil())] =  [0]                                        
                             ?  [4]                                        
                             =  [0()]                                      
                                                                           
           [len(cons(X, Z))] =  [1] Z + [0]                                
                             >= [1] Z + [0]                                
                             =  [s(n__len(activate(Z)))]                   
                                                                           

Further, it can be verified that all rules not oriented are covered by the weightgap condition.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict Trs:
  { fst(X1, X2) -> n__fst(X1, X2)
  , fst(s(X), cons(Y, Z)) ->
    cons(Y, n__fst(activate(X), activate(Z)))
  , activate(X) -> X
  , activate(n__fst(X1, X2)) -> fst(X1, X2)
  , activate(n__from(X)) -> from(X)
  , activate(n__add(X1, X2)) -> add(X1, X2)
  , activate(n__len(X)) -> len(X)
  , add(X1, X2) -> n__add(X1, X2)
  , add(s(X), Y) -> s(n__add(activate(X), Y))
  , len(X) -> n__len(X)
  , len(nil()) -> 0()
  , len(cons(X, Z)) -> s(n__len(activate(Z))) }
Weak Trs:
  { fst(0(), Z) -> nil()
  , from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , add(0(), X) -> X }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

We use the processor 'matrix interpretation of dimension 1' to
orient following rules strictly.

Trs: { len(nil()) -> 0() }

The induced complexity on above rules (modulo remaining rules) is
YES(?,O(n^1)) . These rules are moved into the corresponding weak
component(s).

Sub-proof:
----------
  The following argument positions are usable:
    Uargs(s) = {1}, Uargs(cons) = {2}, Uargs(n__fst) = {1, 2},
    Uargs(n__add) = {1}, Uargs(n__len) = {1}
  
  TcT has computed the following constructor-based matrix
  interpretation satisfying not(EDA).
  
       [fst](x1, x2) = [1] x1 + [1] x2 + [0]
                                            
                 [0] = [0]                  
                                            
               [nil] = [0]                  
                                            
             [s](x1) = [1] x1 + [0]         
                                            
      [cons](x1, x2) = [1] x2 + [0]         
                                            
    [n__fst](x1, x2) = [1] x1 + [1] x2 + [0]
                                            
      [activate](x1) = [1] x1 + [0]         
                                            
          [from](x1) = [0]                  
                                            
       [n__from](x1) = [0]                  
                                            
       [add](x1, x2) = [1] x1 + [1] x2 + [0]
                                            
    [n__add](x1, x2) = [1] x1 + [1] x2 + [0]
                                            
           [len](x1) = [1] x1 + [1]         
                                            
        [n__len](x1) = [1] x1 + [1]         
  
  The order satisfies the following ordering constraints:
  
                 [fst(X1, X2)] =  [1] X1 + [1] X2 + [0]                      
                               >= [1] X1 + [1] X2 + [0]                      
                               =  [n__fst(X1, X2)]                           
                                                                             
                 [fst(0(), Z)] =  [1] Z + [0]                                
                               >= [0]                                        
                               =  [nil()]                                    
                                                                             
       [fst(s(X), cons(Y, Z))] =  [1] Z + [1] X + [0]                        
                               >= [1] Z + [1] X + [0]                        
                               =  [cons(Y, n__fst(activate(X), activate(Z)))]
                                                                             
                 [activate(X)] =  [1] X + [0]                                
                               >= [1] X + [0]                                
                               =  [X]                                        
                                                                             
    [activate(n__fst(X1, X2))] =  [1] X1 + [1] X2 + [0]                      
                               >= [1] X1 + [1] X2 + [0]                      
                               =  [fst(X1, X2)]                              
                                                                             
        [activate(n__from(X))] =  [0]                                        
                               >= [0]                                        
                               =  [from(X)]                                  
                                                                             
    [activate(n__add(X1, X2))] =  [1] X1 + [1] X2 + [0]                      
                               >= [1] X1 + [1] X2 + [0]                      
                               =  [add(X1, X2)]                              
                                                                             
         [activate(n__len(X))] =  [1] X + [1]                                
                               >= [1] X + [1]                                
                               =  [len(X)]                                   
                                                                             
                     [from(X)] =  [0]                                        
                               >= [0]                                        
                               =  [cons(X, n__from(s(X)))]                   
                                                                             
                     [from(X)] =  [0]                                        
                               >= [0]                                        
                               =  [n__from(X)]                               
                                                                             
                 [add(X1, X2)] =  [1] X1 + [1] X2 + [0]                      
                               >= [1] X1 + [1] X2 + [0]                      
                               =  [n__add(X1, X2)]                           
                                                                             
                 [add(0(), X)] =  [1] X + [0]                                
                               >= [1] X + [0]                                
                               =  [X]                                        
                                                                             
                [add(s(X), Y)] =  [1] X + [1] Y + [0]                        
                               >= [1] X + [1] Y + [0]                        
                               =  [s(n__add(activate(X), Y))]                
                                                                             
                      [len(X)] =  [1] X + [1]                                
                               >= [1] X + [1]                                
                               =  [n__len(X)]                                
                                                                             
                  [len(nil())] =  [1]                                        
                               >  [0]                                        
                               =  [0()]                                      
                                                                             
             [len(cons(X, Z))] =  [1] Z + [1]                                
                               >= [1] Z + [1]                                
                               =  [s(n__len(activate(Z)))]                   
                                                                             

We return to the main proof.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict Trs:
  { fst(X1, X2) -> n__fst(X1, X2)
  , fst(s(X), cons(Y, Z)) ->
    cons(Y, n__fst(activate(X), activate(Z)))
  , activate(X) -> X
  , activate(n__fst(X1, X2)) -> fst(X1, X2)
  , activate(n__from(X)) -> from(X)
  , activate(n__add(X1, X2)) -> add(X1, X2)
  , activate(n__len(X)) -> len(X)
  , add(X1, X2) -> n__add(X1, X2)
  , add(s(X), Y) -> s(n__add(activate(X), Y))
  , len(X) -> n__len(X)
  , len(cons(X, Z)) -> s(n__len(activate(Z))) }
Weak Trs:
  { fst(0(), Z) -> nil()
  , from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , add(0(), X) -> X
  , len(nil()) -> 0() }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

The weightgap principle applies (using the following nonconstant
growth matrix-interpretation)

The following argument positions are usable:
  Uargs(s) = {1}, Uargs(cons) = {2}, Uargs(n__fst) = {1, 2},
  Uargs(n__add) = {1}, Uargs(n__len) = {1}

TcT has computed the following matrix interpretation satisfying
not(EDA) and not(IDA(1)).

     [fst](x1, x2) = [1] x1 + [1] x2 + [5]
                                          
               [0] = [3]                  
                                          
             [nil] = [4]                  
                                          
           [s](x1) = [1] x1 + [0]         
                                          
    [cons](x1, x2) = [1] x2 + [0]         
                                          
  [n__fst](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
    [activate](x1) = [1] x1 + [0]         
                                          
        [from](x1) = [5]                  
                                          
     [n__from](x1) = [0]                  
                                          
     [add](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
  [n__add](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
         [len](x1) = [1] x1 + [0]         
                                          
      [n__len](x1) = [1] x1 + [0]         

The order satisfies the following ordering constraints:

               [fst(X1, X2)] =  [1] X1 + [1] X2 + [5]                      
                             >  [1] X1 + [1] X2 + [0]                      
                             =  [n__fst(X1, X2)]                           
                                                                           
               [fst(0(), Z)] =  [1] Z + [8]                                
                             >  [4]                                        
                             =  [nil()]                                    
                                                                           
     [fst(s(X), cons(Y, Z))] =  [1] Z + [1] X + [5]                        
                             >  [1] Z + [1] X + [0]                        
                             =  [cons(Y, n__fst(activate(X), activate(Z)))]
                                                                           
               [activate(X)] =  [1] X + [0]                                
                             >= [1] X + [0]                                
                             =  [X]                                        
                                                                           
  [activate(n__fst(X1, X2))] =  [1] X1 + [1] X2 + [0]                      
                             ?  [1] X1 + [1] X2 + [5]                      
                             =  [fst(X1, X2)]                              
                                                                           
      [activate(n__from(X))] =  [0]                                        
                             ?  [5]                                        
                             =  [from(X)]                                  
                                                                           
  [activate(n__add(X1, X2))] =  [1] X1 + [1] X2 + [0]                      
                             >= [1] X1 + [1] X2 + [0]                      
                             =  [add(X1, X2)]                              
                                                                           
       [activate(n__len(X))] =  [1] X + [0]                                
                             >= [1] X + [0]                                
                             =  [len(X)]                                   
                                                                           
                   [from(X)] =  [5]                                        
                             >  [0]                                        
                             =  [cons(X, n__from(s(X)))]                   
                                                                           
                   [from(X)] =  [5]                                        
                             >  [0]                                        
                             =  [n__from(X)]                               
                                                                           
               [add(X1, X2)] =  [1] X1 + [1] X2 + [0]                      
                             >= [1] X1 + [1] X2 + [0]                      
                             =  [n__add(X1, X2)]                           
                                                                           
               [add(0(), X)] =  [1] X + [3]                                
                             >  [1] X + [0]                                
                             =  [X]                                        
                                                                           
              [add(s(X), Y)] =  [1] X + [1] Y + [0]                        
                             >= [1] X + [1] Y + [0]                        
                             =  [s(n__add(activate(X), Y))]                
                                                                           
                    [len(X)] =  [1] X + [0]                                
                             >= [1] X + [0]                                
                             =  [n__len(X)]                                
                                                                           
                [len(nil())] =  [4]                                        
                             >  [3]                                        
                             =  [0()]                                      
                                                                           
           [len(cons(X, Z))] =  [1] Z + [0]                                
                             >= [1] Z + [0]                                
                             =  [s(n__len(activate(Z)))]                   
                                                                           

Further, it can be verified that all rules not oriented are covered by the weightgap condition.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict Trs:
  { activate(X) -> X
  , activate(n__fst(X1, X2)) -> fst(X1, X2)
  , activate(n__from(X)) -> from(X)
  , activate(n__add(X1, X2)) -> add(X1, X2)
  , activate(n__len(X)) -> len(X)
  , add(X1, X2) -> n__add(X1, X2)
  , add(s(X), Y) -> s(n__add(activate(X), Y))
  , len(X) -> n__len(X)
  , len(cons(X, Z)) -> s(n__len(activate(Z))) }
Weak Trs:
  { fst(X1, X2) -> n__fst(X1, X2)
  , fst(0(), Z) -> nil()
  , fst(s(X), cons(Y, Z)) ->
    cons(Y, n__fst(activate(X), activate(Z)))
  , from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , add(0(), X) -> X
  , len(nil()) -> 0() }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

We use the processor 'matrix interpretation of dimension 1' to
orient following rules strictly.

Trs:
  { activate(n__len(X)) -> len(X)
  , add(s(X), Y) -> s(n__add(activate(X), Y))
  , len(X) -> n__len(X)
  , len(cons(X, Z)) -> s(n__len(activate(Z))) }

The induced complexity on above rules (modulo remaining rules) is
YES(?,O(n^1)) . These rules are moved into the corresponding weak
component(s).

Sub-proof:
----------
  The following argument positions are usable:
    Uargs(s) = {1}, Uargs(cons) = {2}, Uargs(n__fst) = {1, 2},
    Uargs(n__add) = {1}, Uargs(n__len) = {1}
  
  TcT has computed the following constructor-based matrix
  interpretation satisfying not(EDA).
  
       [fst](x1, x2) = [4] x1 + [4] x2 + [0]
                                            
                 [0] = [0]                  
                                            
               [nil] = [0]                  
                                            
             [s](x1) = [1] x1 + [2]         
                                            
      [cons](x1, x2) = [1] x2 + [0]         
                                            
    [n__fst](x1, x2) = [1] x1 + [1] x2 + [0]
                                            
      [activate](x1) = [4] x1 + [0]         
                                            
          [from](x1) = [0]                  
                                            
       [n__from](x1) = [0]                  
                                            
       [add](x1, x2) = [4] x1 + [2] x2 + [0]
                                            
    [n__add](x1, x2) = [1] x1 + [1] x2 + [0]
                                            
           [len](x1) = [4] x1 + [5]         
                                            
        [n__len](x1) = [1] x1 + [2]         
  
  The order satisfies the following ordering constraints:
  
                 [fst(X1, X2)] =  [4] X1 + [4] X2 + [0]                      
                               >= [1] X1 + [1] X2 + [0]                      
                               =  [n__fst(X1, X2)]                           
                                                                             
                 [fst(0(), Z)] =  [4] Z + [0]                                
                               >= [0]                                        
                               =  [nil()]                                    
                                                                             
       [fst(s(X), cons(Y, Z))] =  [4] Z + [4] X + [8]                        
                               >  [4] Z + [4] X + [0]                        
                               =  [cons(Y, n__fst(activate(X), activate(Z)))]
                                                                             
                 [activate(X)] =  [4] X + [0]                                
                               >= [1] X + [0]                                
                               =  [X]                                        
                                                                             
    [activate(n__fst(X1, X2))] =  [4] X1 + [4] X2 + [0]                      
                               >= [4] X1 + [4] X2 + [0]                      
                               =  [fst(X1, X2)]                              
                                                                             
        [activate(n__from(X))] =  [0]                                        
                               >= [0]                                        
                               =  [from(X)]                                  
                                                                             
    [activate(n__add(X1, X2))] =  [4] X1 + [4] X2 + [0]                      
                               >= [4] X1 + [2] X2 + [0]                      
                               =  [add(X1, X2)]                              
                                                                             
         [activate(n__len(X))] =  [4] X + [8]                                
                               >  [4] X + [5]                                
                               =  [len(X)]                                   
                                                                             
                     [from(X)] =  [0]                                        
                               >= [0]                                        
                               =  [cons(X, n__from(s(X)))]                   
                                                                             
                     [from(X)] =  [0]                                        
                               >= [0]                                        
                               =  [n__from(X)]                               
                                                                             
                 [add(X1, X2)] =  [4] X1 + [2] X2 + [0]                      
                               >= [1] X1 + [1] X2 + [0]                      
                               =  [n__add(X1, X2)]                           
                                                                             
                 [add(0(), X)] =  [2] X + [0]                                
                               >= [1] X + [0]                                
                               =  [X]                                        
                                                                             
                [add(s(X), Y)] =  [4] X + [2] Y + [8]                        
                               >  [4] X + [1] Y + [2]                        
                               =  [s(n__add(activate(X), Y))]                
                                                                             
                      [len(X)] =  [4] X + [5]                                
                               >  [1] X + [2]                                
                               =  [n__len(X)]                                
                                                                             
                  [len(nil())] =  [5]                                        
                               >  [0]                                        
                               =  [0()]                                      
                                                                             
             [len(cons(X, Z))] =  [4] Z + [5]                                
                               >  [4] Z + [4]                                
                               =  [s(n__len(activate(Z)))]                   
                                                                             

We return to the main proof.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict Trs:
  { activate(X) -> X
  , activate(n__fst(X1, X2)) -> fst(X1, X2)
  , activate(n__from(X)) -> from(X)
  , activate(n__add(X1, X2)) -> add(X1, X2)
  , add(X1, X2) -> n__add(X1, X2) }
Weak Trs:
  { fst(X1, X2) -> n__fst(X1, X2)
  , fst(0(), Z) -> nil()
  , fst(s(X), cons(Y, Z)) ->
    cons(Y, n__fst(activate(X), activate(Z)))
  , activate(n__len(X)) -> len(X)
  , from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , add(0(), X) -> X
  , add(s(X), Y) -> s(n__add(activate(X), Y))
  , len(X) -> n__len(X)
  , len(nil()) -> 0()
  , len(cons(X, Z)) -> s(n__len(activate(Z))) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

The weightgap principle applies (using the following nonconstant
growth matrix-interpretation)

The following argument positions are usable:
  Uargs(s) = {1}, Uargs(cons) = {2}, Uargs(n__fst) = {1, 2},
  Uargs(n__add) = {1}, Uargs(n__len) = {1}

TcT has computed the following matrix interpretation satisfying
not(EDA) and not(IDA(1)).

     [fst](x1, x2) = [1] x1 + [1] x2 + [5]
                                          
               [0] = [3]                  
                                          
             [nil] = [4]                  
                                          
           [s](x1) = [1] x1 + [0]         
                                          
    [cons](x1, x2) = [1] x2 + [0]         
                                          
  [n__fst](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
    [activate](x1) = [1] x1 + [0]         
                                          
        [from](x1) = [7]                  
                                          
     [n__from](x1) = [0]                  
                                          
     [add](x1, x2) = [1] x1 + [1] x2 + [4]
                                          
  [n__add](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
         [len](x1) = [1] x1 + [0]         
                                          
      [n__len](x1) = [1] x1 + [0]         

The order satisfies the following ordering constraints:

               [fst(X1, X2)] =  [1] X1 + [1] X2 + [5]                      
                             >  [1] X1 + [1] X2 + [0]                      
                             =  [n__fst(X1, X2)]                           
                                                                           
               [fst(0(), Z)] =  [1] Z + [8]                                
                             >  [4]                                        
                             =  [nil()]                                    
                                                                           
     [fst(s(X), cons(Y, Z))] =  [1] Z + [1] X + [5]                        
                             >  [1] Z + [1] X + [0]                        
                             =  [cons(Y, n__fst(activate(X), activate(Z)))]
                                                                           
               [activate(X)] =  [1] X + [0]                                
                             >= [1] X + [0]                                
                             =  [X]                                        
                                                                           
  [activate(n__fst(X1, X2))] =  [1] X1 + [1] X2 + [0]                      
                             ?  [1] X1 + [1] X2 + [5]                      
                             =  [fst(X1, X2)]                              
                                                                           
      [activate(n__from(X))] =  [0]                                        
                             ?  [7]                                        
                             =  [from(X)]                                  
                                                                           
  [activate(n__add(X1, X2))] =  [1] X1 + [1] X2 + [0]                      
                             ?  [1] X1 + [1] X2 + [4]                      
                             =  [add(X1, X2)]                              
                                                                           
       [activate(n__len(X))] =  [1] X + [0]                                
                             >= [1] X + [0]                                
                             =  [len(X)]                                   
                                                                           
                   [from(X)] =  [7]                                        
                             >  [0]                                        
                             =  [cons(X, n__from(s(X)))]                   
                                                                           
                   [from(X)] =  [7]                                        
                             >  [0]                                        
                             =  [n__from(X)]                               
                                                                           
               [add(X1, X2)] =  [1] X1 + [1] X2 + [4]                      
                             >  [1] X1 + [1] X2 + [0]                      
                             =  [n__add(X1, X2)]                           
                                                                           
               [add(0(), X)] =  [1] X + [7]                                
                             >  [1] X + [0]                                
                             =  [X]                                        
                                                                           
              [add(s(X), Y)] =  [1] X + [1] Y + [4]                        
                             >  [1] X + [1] Y + [0]                        
                             =  [s(n__add(activate(X), Y))]                
                                                                           
                    [len(X)] =  [1] X + [0]                                
                             >= [1] X + [0]                                
                             =  [n__len(X)]                                
                                                                           
                [len(nil())] =  [4]                                        
                             >  [3]                                        
                             =  [0()]                                      
                                                                           
           [len(cons(X, Z))] =  [1] Z + [0]                                
                             >= [1] Z + [0]                                
                             =  [s(n__len(activate(Z)))]                   
                                                                           

Further, it can be verified that all rules not oriented are covered by the weightgap condition.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict Trs:
  { activate(X) -> X
  , activate(n__fst(X1, X2)) -> fst(X1, X2)
  , activate(n__from(X)) -> from(X)
  , activate(n__add(X1, X2)) -> add(X1, X2) }
Weak Trs:
  { fst(X1, X2) -> n__fst(X1, X2)
  , fst(0(), Z) -> nil()
  , fst(s(X), cons(Y, Z)) ->
    cons(Y, n__fst(activate(X), activate(Z)))
  , activate(n__len(X)) -> len(X)
  , from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , add(X1, X2) -> n__add(X1, X2)
  , add(0(), X) -> X
  , add(s(X), Y) -> s(n__add(activate(X), Y))
  , len(X) -> n__len(X)
  , len(nil()) -> 0()
  , len(cons(X, Z)) -> s(n__len(activate(Z))) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

The weightgap principle applies (using the following nonconstant
growth matrix-interpretation)

The following argument positions are usable:
  Uargs(s) = {1}, Uargs(cons) = {2}, Uargs(n__fst) = {1, 2},
  Uargs(n__add) = {1}, Uargs(n__len) = {1}

TcT has computed the following matrix interpretation satisfying
not(EDA) and not(IDA(1)).

     [fst](x1, x2) = [1] x1 + [1] x2 + [5]
                                          
               [0] = [0]                  
                                          
             [nil] = [0]                  
                                          
           [s](x1) = [1] x1 + [1]         
                                          
    [cons](x1, x2) = [1] x2 + [2]         
                                          
  [n__fst](x1, x2) = [1] x1 + [1] x2 + [2]
                                          
    [activate](x1) = [1] x1 + [2]         
                                          
        [from](x1) = [5]                  
                                          
     [n__from](x1) = [3]                  
                                          
     [add](x1, x2) = [1] x1 + [1] x2 + [7]
                                          
  [n__add](x1, x2) = [1] x1 + [1] x2 + [2]
                                          
         [len](x1) = [1] x1 + [4]         
                                          
      [n__len](x1) = [1] x1 + [2]         

The order satisfies the following ordering constraints:

               [fst(X1, X2)] =  [1] X1 + [1] X2 + [5]                      
                             >  [1] X1 + [1] X2 + [2]                      
                             =  [n__fst(X1, X2)]                           
                                                                           
               [fst(0(), Z)] =  [1] Z + [5]                                
                             >  [0]                                        
                             =  [nil()]                                    
                                                                           
     [fst(s(X), cons(Y, Z))] =  [1] Z + [1] X + [8]                        
                             >= [1] Z + [1] X + [8]                        
                             =  [cons(Y, n__fst(activate(X), activate(Z)))]
                                                                           
               [activate(X)] =  [1] X + [2]                                
                             >  [1] X + [0]                                
                             =  [X]                                        
                                                                           
  [activate(n__fst(X1, X2))] =  [1] X1 + [1] X2 + [4]                      
                             ?  [1] X1 + [1] X2 + [5]                      
                             =  [fst(X1, X2)]                              
                                                                           
      [activate(n__from(X))] =  [5]                                        
                             >= [5]                                        
                             =  [from(X)]                                  
                                                                           
  [activate(n__add(X1, X2))] =  [1] X1 + [1] X2 + [4]                      
                             ?  [1] X1 + [1] X2 + [7]                      
                             =  [add(X1, X2)]                              
                                                                           
       [activate(n__len(X))] =  [1] X + [4]                                
                             >= [1] X + [4]                                
                             =  [len(X)]                                   
                                                                           
                   [from(X)] =  [5]                                        
                             >= [5]                                        
                             =  [cons(X, n__from(s(X)))]                   
                                                                           
                   [from(X)] =  [5]                                        
                             >  [3]                                        
                             =  [n__from(X)]                               
                                                                           
               [add(X1, X2)] =  [1] X1 + [1] X2 + [7]                      
                             >  [1] X1 + [1] X2 + [2]                      
                             =  [n__add(X1, X2)]                           
                                                                           
               [add(0(), X)] =  [1] X + [7]                                
                             >  [1] X + [0]                                
                             =  [X]                                        
                                                                           
              [add(s(X), Y)] =  [1] X + [1] Y + [8]                        
                             >  [1] X + [1] Y + [5]                        
                             =  [s(n__add(activate(X), Y))]                
                                                                           
                    [len(X)] =  [1] X + [4]                                
                             >  [1] X + [2]                                
                             =  [n__len(X)]                                
                                                                           
                [len(nil())] =  [4]                                        
                             >  [0]                                        
                             =  [0()]                                      
                                                                           
           [len(cons(X, Z))] =  [1] Z + [6]                                
                             >  [1] Z + [5]                                
                             =  [s(n__len(activate(Z)))]                   
                                                                           

Further, it can be verified that all rules not oriented are covered by the weightgap condition.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict Trs:
  { activate(n__fst(X1, X2)) -> fst(X1, X2)
  , activate(n__from(X)) -> from(X)
  , activate(n__add(X1, X2)) -> add(X1, X2) }
Weak Trs:
  { fst(X1, X2) -> n__fst(X1, X2)
  , fst(0(), Z) -> nil()
  , fst(s(X), cons(Y, Z)) ->
    cons(Y, n__fst(activate(X), activate(Z)))
  , activate(X) -> X
  , activate(n__len(X)) -> len(X)
  , from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , add(X1, X2) -> n__add(X1, X2)
  , add(0(), X) -> X
  , add(s(X), Y) -> s(n__add(activate(X), Y))
  , len(X) -> n__len(X)
  , len(nil()) -> 0()
  , len(cons(X, Z)) -> s(n__len(activate(Z))) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

The weightgap principle applies (using the following nonconstant
growth matrix-interpretation)

The following argument positions are usable:
  Uargs(s) = {1}, Uargs(cons) = {2}, Uargs(n__fst) = {1, 2},
  Uargs(n__add) = {1}, Uargs(n__len) = {1}

TcT has computed the following matrix interpretation satisfying
not(EDA) and not(IDA(1)).

     [fst](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
               [0] = [2]                  
                                          
             [nil] = [0]                  
                                          
           [s](x1) = [1] x1 + [5]         
                                          
    [cons](x1, x2) = [1] x2 + [6]         
                                          
  [n__fst](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
    [activate](x1) = [1] x1 + [1]         
                                          
        [from](x1) = [7]                  
                                          
     [n__from](x1) = [0]                  
                                          
     [add](x1, x2) = [1] x1 + [1] x2 + [4]
                                          
  [n__add](x1, x2) = [1] x1 + [1] x2 + [0]
                                          
         [len](x1) = [1] x1 + [4]         
                                          
      [n__len](x1) = [1] x1 + [4]         

The order satisfies the following ordering constraints:

               [fst(X1, X2)] =  [1] X1 + [1] X2 + [0]                      
                             >= [1] X1 + [1] X2 + [0]                      
                             =  [n__fst(X1, X2)]                           
                                                                           
               [fst(0(), Z)] =  [1] Z + [2]                                
                             >  [0]                                        
                             =  [nil()]                                    
                                                                           
     [fst(s(X), cons(Y, Z))] =  [1] Z + [1] X + [11]                       
                             >  [1] Z + [1] X + [8]                        
                             =  [cons(Y, n__fst(activate(X), activate(Z)))]
                                                                           
               [activate(X)] =  [1] X + [1]                                
                             >  [1] X + [0]                                
                             =  [X]                                        
                                                                           
  [activate(n__fst(X1, X2))] =  [1] X1 + [1] X2 + [1]                      
                             >  [1] X1 + [1] X2 + [0]                      
                             =  [fst(X1, X2)]                              
                                                                           
      [activate(n__from(X))] =  [1]                                        
                             ?  [7]                                        
                             =  [from(X)]                                  
                                                                           
  [activate(n__add(X1, X2))] =  [1] X1 + [1] X2 + [1]                      
                             ?  [1] X1 + [1] X2 + [4]                      
                             =  [add(X1, X2)]                              
                                                                           
       [activate(n__len(X))] =  [1] X + [5]                                
                             >  [1] X + [4]                                
                             =  [len(X)]                                   
                                                                           
                   [from(X)] =  [7]                                        
                             >  [6]                                        
                             =  [cons(X, n__from(s(X)))]                   
                                                                           
                   [from(X)] =  [7]                                        
                             >  [0]                                        
                             =  [n__from(X)]                               
                                                                           
               [add(X1, X2)] =  [1] X1 + [1] X2 + [4]                      
                             >  [1] X1 + [1] X2 + [0]                      
                             =  [n__add(X1, X2)]                           
                                                                           
               [add(0(), X)] =  [1] X + [6]                                
                             >  [1] X + [0]                                
                             =  [X]                                        
                                                                           
              [add(s(X), Y)] =  [1] X + [1] Y + [9]                        
                             >  [1] X + [1] Y + [6]                        
                             =  [s(n__add(activate(X), Y))]                
                                                                           
                    [len(X)] =  [1] X + [4]                                
                             >= [1] X + [4]                                
                             =  [n__len(X)]                                
                                                                           
                [len(nil())] =  [4]                                        
                             >  [2]                                        
                             =  [0()]                                      
                                                                           
           [len(cons(X, Z))] =  [1] Z + [10]                               
                             >= [1] Z + [10]                               
                             =  [s(n__len(activate(Z)))]                   
                                                                           

Further, it can be verified that all rules not oriented are covered by the weightgap condition.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict Trs:
  { activate(n__from(X)) -> from(X)
  , activate(n__add(X1, X2)) -> add(X1, X2) }
Weak Trs:
  { fst(X1, X2) -> n__fst(X1, X2)
  , fst(0(), Z) -> nil()
  , fst(s(X), cons(Y, Z)) ->
    cons(Y, n__fst(activate(X), activate(Z)))
  , activate(X) -> X
  , activate(n__fst(X1, X2)) -> fst(X1, X2)
  , activate(n__len(X)) -> len(X)
  , from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , add(X1, X2) -> n__add(X1, X2)
  , add(0(), X) -> X
  , add(s(X), Y) -> s(n__add(activate(X), Y))
  , len(X) -> n__len(X)
  , len(nil()) -> 0()
  , len(cons(X, Z)) -> s(n__len(activate(Z))) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

We use the processor 'matrix interpretation of dimension 1' to
orient following rules strictly.

Trs: { activate(n__add(X1, X2)) -> add(X1, X2) }

The induced complexity on above rules (modulo remaining rules) is
YES(?,O(n^1)) . These rules are moved into the corresponding weak
component(s).

Sub-proof:
----------
  The following argument positions are usable:
    Uargs(s) = {1}, Uargs(cons) = {2}, Uargs(n__fst) = {1, 2},
    Uargs(n__add) = {1}, Uargs(n__len) = {1}
  
  TcT has computed the following constructor-based matrix
  interpretation satisfying not(EDA).
  
       [fst](x1, x2) = [3] x1 + [3] x2 + [0]
                                            
                 [0] = [0]                  
                                            
               [nil] = [0]                  
                                            
             [s](x1) = [1] x1 + [0]         
                                            
      [cons](x1, x2) = [1] x2 + [0]         
                                            
    [n__fst](x1, x2) = [1] x1 + [1] x2 + [0]
                                            
      [activate](x1) = [3] x1 + [0]         
                                            
          [from](x1) = [0]                  
                                            
       [n__from](x1) = [0]                  
                                            
       [add](x1, x2) = [3] x1 + [1] x2 + [3]
                                            
    [n__add](x1, x2) = [1] x1 + [1] x2 + [3]
                                            
           [len](x1) = [3] x1 + [0]         
                                            
        [n__len](x1) = [1] x1 + [0]         
  
  The order satisfies the following ordering constraints:
  
                 [fst(X1, X2)] =  [3] X1 + [3] X2 + [0]                      
                               >= [1] X1 + [1] X2 + [0]                      
                               =  [n__fst(X1, X2)]                           
                                                                             
                 [fst(0(), Z)] =  [3] Z + [0]                                
                               >= [0]                                        
                               =  [nil()]                                    
                                                                             
       [fst(s(X), cons(Y, Z))] =  [3] Z + [3] X + [0]                        
                               >= [3] Z + [3] X + [0]                        
                               =  [cons(Y, n__fst(activate(X), activate(Z)))]
                                                                             
                 [activate(X)] =  [3] X + [0]                                
                               >= [1] X + [0]                                
                               =  [X]                                        
                                                                             
    [activate(n__fst(X1, X2))] =  [3] X1 + [3] X2 + [0]                      
                               >= [3] X1 + [3] X2 + [0]                      
                               =  [fst(X1, X2)]                              
                                                                             
        [activate(n__from(X))] =  [0]                                        
                               >= [0]                                        
                               =  [from(X)]                                  
                                                                             
    [activate(n__add(X1, X2))] =  [3] X1 + [3] X2 + [9]                      
                               >  [3] X1 + [1] X2 + [3]                      
                               =  [add(X1, X2)]                              
                                                                             
         [activate(n__len(X))] =  [3] X + [0]                                
                               >= [3] X + [0]                                
                               =  [len(X)]                                   
                                                                             
                     [from(X)] =  [0]                                        
                               >= [0]                                        
                               =  [cons(X, n__from(s(X)))]                   
                                                                             
                     [from(X)] =  [0]                                        
                               >= [0]                                        
                               =  [n__from(X)]                               
                                                                             
                 [add(X1, X2)] =  [3] X1 + [1] X2 + [3]                      
                               >= [1] X1 + [1] X2 + [3]                      
                               =  [n__add(X1, X2)]                           
                                                                             
                 [add(0(), X)] =  [1] X + [3]                                
                               >  [1] X + [0]                                
                               =  [X]                                        
                                                                             
                [add(s(X), Y)] =  [3] X + [1] Y + [3]                        
                               >= [3] X + [1] Y + [3]                        
                               =  [s(n__add(activate(X), Y))]                
                                                                             
                      [len(X)] =  [3] X + [0]                                
                               >= [1] X + [0]                                
                               =  [n__len(X)]                                
                                                                             
                  [len(nil())] =  [0]                                        
                               >= [0]                                        
                               =  [0()]                                      
                                                                             
             [len(cons(X, Z))] =  [3] Z + [0]                                
                               >= [3] Z + [0]                                
                               =  [s(n__len(activate(Z)))]                   
                                                                             

We return to the main proof.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(n^1)).

Strict Trs: { activate(n__from(X)) -> from(X) }
Weak Trs:
  { fst(X1, X2) -> n__fst(X1, X2)
  , fst(0(), Z) -> nil()
  , fst(s(X), cons(Y, Z)) ->
    cons(Y, n__fst(activate(X), activate(Z)))
  , activate(X) -> X
  , activate(n__fst(X1, X2)) -> fst(X1, X2)
  , activate(n__add(X1, X2)) -> add(X1, X2)
  , activate(n__len(X)) -> len(X)
  , from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , add(X1, X2) -> n__add(X1, X2)
  , add(0(), X) -> X
  , add(s(X), Y) -> s(n__add(activate(X), Y))
  , len(X) -> n__len(X)
  , len(nil()) -> 0()
  , len(cons(X, Z)) -> s(n__len(activate(Z))) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(n^1))

We use the processor 'matrix interpretation of dimension 1' to
orient following rules strictly.

Trs: { activate(n__from(X)) -> from(X) }

The induced complexity on above rules (modulo remaining rules) is
YES(?,O(n^1)) . These rules are moved into the corresponding weak
component(s).

Sub-proof:
----------
  The following argument positions are usable:
    Uargs(s) = {1}, Uargs(cons) = {2}, Uargs(n__fst) = {1, 2},
    Uargs(n__add) = {1}, Uargs(n__len) = {1}
  
  TcT has computed the following constructor-based matrix
  interpretation satisfying not(EDA).
  
       [fst](x1, x2) = [2] x1 + [2] x2 + [0]
                                            
                 [0] = [0]                  
                                            
               [nil] = [0]                  
                                            
             [s](x1) = [1] x1 + [1]         
                                            
      [cons](x1, x2) = [1] x2 + [1]         
                                            
    [n__fst](x1, x2) = [1] x1 + [1] x2 + [0]
                                            
      [activate](x1) = [2] x1 + [0]         
                                            
          [from](x1) = [6]                  
                                            
       [n__from](x1) = [4]                  
                                            
       [add](x1, x2) = [2] x1 + [2] x2 + [5]
                                            
    [n__add](x1, x2) = [1] x1 + [1] x2 + [4]
                                            
           [len](x1) = [2] x1 + [0]         
                                            
        [n__len](x1) = [1] x1 + [0]         
  
  The order satisfies the following ordering constraints:
  
                 [fst(X1, X2)] =  [2] X1 + [2] X2 + [0]                      
                               >= [1] X1 + [1] X2 + [0]                      
                               =  [n__fst(X1, X2)]                           
                                                                             
                 [fst(0(), Z)] =  [2] Z + [0]                                
                               >= [0]                                        
                               =  [nil()]                                    
                                                                             
       [fst(s(X), cons(Y, Z))] =  [2] Z + [2] X + [4]                        
                               >  [2] Z + [2] X + [1]                        
                               =  [cons(Y, n__fst(activate(X), activate(Z)))]
                                                                             
                 [activate(X)] =  [2] X + [0]                                
                               >= [1] X + [0]                                
                               =  [X]                                        
                                                                             
    [activate(n__fst(X1, X2))] =  [2] X1 + [2] X2 + [0]                      
                               >= [2] X1 + [2] X2 + [0]                      
                               =  [fst(X1, X2)]                              
                                                                             
        [activate(n__from(X))] =  [8]                                        
                               >  [6]                                        
                               =  [from(X)]                                  
                                                                             
    [activate(n__add(X1, X2))] =  [2] X1 + [2] X2 + [8]                      
                               >  [2] X1 + [2] X2 + [5]                      
                               =  [add(X1, X2)]                              
                                                                             
         [activate(n__len(X))] =  [2] X + [0]                                
                               >= [2] X + [0]                                
                               =  [len(X)]                                   
                                                                             
                     [from(X)] =  [6]                                        
                               >  [5]                                        
                               =  [cons(X, n__from(s(X)))]                   
                                                                             
                     [from(X)] =  [6]                                        
                               >  [4]                                        
                               =  [n__from(X)]                               
                                                                             
                 [add(X1, X2)] =  [2] X1 + [2] X2 + [5]                      
                               >  [1] X1 + [1] X2 + [4]                      
                               =  [n__add(X1, X2)]                           
                                                                             
                 [add(0(), X)] =  [2] X + [5]                                
                               >  [1] X + [0]                                
                               =  [X]                                        
                                                                             
                [add(s(X), Y)] =  [2] X + [2] Y + [7]                        
                               >  [2] X + [1] Y + [5]                        
                               =  [s(n__add(activate(X), Y))]                
                                                                             
                      [len(X)] =  [2] X + [0]                                
                               >= [1] X + [0]                                
                               =  [n__len(X)]                                
                                                                             
                  [len(nil())] =  [0]                                        
                               >= [0]                                        
                               =  [0()]                                      
                                                                             
             [len(cons(X, Z))] =  [2] Z + [2]                                
                               >  [2] Z + [1]                                
                               =  [s(n__len(activate(Z)))]                   
                                                                             

We return to the main proof.

We are left with following problem, upon which TcT provides the
certificate YES(O(1),O(1)).

Weak Trs:
  { fst(X1, X2) -> n__fst(X1, X2)
  , fst(0(), Z) -> nil()
  , fst(s(X), cons(Y, Z)) ->
    cons(Y, n__fst(activate(X), activate(Z)))
  , activate(X) -> X
  , activate(n__fst(X1, X2)) -> fst(X1, X2)
  , activate(n__from(X)) -> from(X)
  , activate(n__add(X1, X2)) -> add(X1, X2)
  , activate(n__len(X)) -> len(X)
  , from(X) -> cons(X, n__from(s(X)))
  , from(X) -> n__from(X)
  , add(X1, X2) -> n__add(X1, X2)
  , add(0(), X) -> X
  , add(s(X), Y) -> s(n__add(activate(X), Y))
  , len(X) -> n__len(X)
  , len(nil()) -> 0()
  , len(cons(X, Z)) -> s(n__len(activate(Z))) }
Obligation:
  innermost runtime complexity
Answer:
  YES(O(1),O(1))

Empty rules are trivially bounded

Hurray, we answered YES(O(1),O(n^1))